Big Rigs Getting a Good Night's Rest

From both a global environmental and an economic point of view, New Article 626 may be one of the most exciting concepts to ever be proposed for the National Electrical Code (NEC); the proposed electrified truck parking space equipment will provide telephone connections, cable and power for televisions, fax machines, microwaves, coffee pots and a host of other appliances. However, the most exciting provision is the ability of these units to provide heating and cooling (HVAC) for the cabs of the big rigs.

This proposal was developed by a coalition of multi-industry groups formerly named the Truck Stop Electrification (TSE) committee of the National Transportation Infrastructure Working Council (IWC) and was sponsored by the Electric Power Research Institute (EPRI). The TSE committee is a group of professional volunteers, representing truck manufacturers, truck stop designers and implementers, component manufacturers, electric utilities, members of the National Association of Truck Stop Operators and the Society of Automotive Engineers (SAE), the Environmental Protection Agency (EPA), the Department of Energy (DOE), the Department of Defense (DOD), the IEEE, Electric Power Research Institute and others interested in developing this technology.

Why have all of these heavy hitters in American industry and government come together to develop this new technology and work so hard to put it into the NEC? Anyone who has ever driven into any truck stop in the United States has heard the big-rig trucks sitting with their engines idling. Most people, however, do not realize the major amounts of diesel fuel they are burning, the emissions produced from this idling and the cost of maintenance involved. For most on-road, heavy-duty trucking fleets, idling can account for more than 50 percent of the total trip time. For example, a Class 8 truck (one of the big rigs) typically idles 10 to 12 hours per night for about 300 nights per year or approximately 3,000 hours per year. Consider that there are approximately 1.4 million heavy-duty long haul trucks on the road. If each truck emits more than 0.3 tons of nitrogen oxide and 21 tons of carbon dioxide, among other pollutants, the overall emission is 420,000 tons of nitrogen oxide and 29,400,000 tons of carbon dioxide.

In addition, a typical diesel truck burns 1 to 1.3 gallons of fuel at idle each hour with total yearly fuel consumption of 1.2 billion gallons for the 1.4 million trucks idling at truck stops and other stopping points along the highways. The overall yearly cost of this fuel is more than $1 trillion to the trucking industry and, ultimately, to all consumers, since we are buying the goods being trucked across the country.

The wear and tear on a truck idling for one hour is equivalent to being driven about seven miles and, since the idling truck has less air to cool the engine oil, the operating life of the oil is reduced by 75 percent or reduced from a usable life of 600 hours to about 150 hours.

For these reasons, regulatory agencies and environmental groups have focused on reducing truck idling, and a major part of this effort has been spent developing a standardized, safe and efficient means of reducing fuel consumption and emissions. More than 20 states and cities have already adopted legislation to reduce the amount of idling for heavy trucks, so by developing the installation requirements for electrification of truck parking spaces, this new Article 626 is very timely and an extremely important piece of the puzzle.

The scope of Article 626 provides the necessary information and provisions to cover electrified truck parking spaces and reads: “626.1 Scope. The provisions of this article cover the electrical conductors and equipment external to the truck or transport refrigerated unit that connect trucks or transport refrigerated units to a supply of electricity, and the installation of equipment and devices related to electrical installations within an electrified truck parking space.” The specific wording of the scope statement will ensure that the NEC covers the power external to the truck, including any gantry (e.g., the overhead support structure) necessary to support the wiring, HVAC and other components. Any new article requires specific definitions, and the following is the definition for an electrified truck parking space: “A truck parking space that has been provided with an electrical system that allows truckers to ‘plug in’ their vehicles while stopped, and use off-board power sources in order to operate on-board systems, such as air conditioning, heating and appliances, without any engine idling.” A fine print note has been added to help identify those areas that are and that are not considered to be “electrified truck parking spaces.”

Review this new article and find a potentially lucrative electrical installation opportunity.     EC

ODE is a staff engineering associate at Underwriters Laboratories Inc., in Research Triangle Park, N.C. He can be reached at 919.549.1726 or via e-mail at


About the Author

Mark C. Ode

Fire/Life Safety Columnist and Code Contributor
Mark C. Ode is a lead engineering associate for Energy & Power Technologies at Underwriters Laboratories Inc. and can be reached at 919.949.2576 and .

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